Associated Press: Two of the most important Greenhouse gases in the Earth’s atmosphere reached a record high in 2006, and measurements show that one – carbon dioxide – is playing an increasingly important role in global warming, the U.N. weather agency said Friday. The global average concentrations of carbon dioxide, or CO2, and nitrous oxide, or N2O, in the atmosphere were higher than ever in measurements coordinated by the World Meteorological Organization, said Geir Braathen, a climate specialist at …